EP0042897B1 - Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters - Google Patents

Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters Download PDF

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Publication number
EP0042897B1
EP0042897B1 EP19800302225 EP80302225A EP0042897B1 EP 0042897 B1 EP0042897 B1 EP 0042897B1 EP 19800302225 EP19800302225 EP 19800302225 EP 80302225 A EP80302225 A EP 80302225A EP 0042897 B1 EP0042897 B1 EP 0042897B1
Authority
EP
European Patent Office
Prior art keywords
lining
vessel
slurry
molten metal
moulding
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19800302225
Other languages
English (en)
French (fr)
Other versions
EP0042897A1 (de
Inventor
Masaru Takashima
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aikoh Co Ltd
Original Assignee
Aikoh Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Aikoh Co Ltd filed Critical Aikoh Co Ltd
Priority to DE8080302225T priority Critical patent/DE3069065D1/de
Priority to EP19800302225 priority patent/EP0042897B1/de
Publication of EP0042897A1 publication Critical patent/EP0042897A1/de
Application granted granted Critical
Publication of EP0042897B1 publication Critical patent/EP0042897B1/de
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/6303—Inorganic additives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
    • B22D41/02—Linings
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/03—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite
    • C04B35/04—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on magnesium oxide, calcium oxide or oxide mixtures derived from dolomite based on magnesium oxide
    • C04B35/043—Refractories from grain sized mixtures
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/626—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B
    • C04B35/63—Preparing or treating the powders individually or as batches ; preparing or treating macroscopic reinforcing agents for ceramic products, e.g. fibres; mechanical aspects section B using additives specially adapted for forming the products, e.g.. binder binders
    • C04B35/632—Organic additives
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/66—Monolithic refractories or refractory mortars, including those whether or not containing clay
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/71—Ceramic products containing macroscopic reinforcing agents
    • C04B35/74—Ceramic products containing macroscopic reinforcing agents containing shaped metallic materials
    • C04B35/76—Fibres, filaments, whiskers, platelets, or the like
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00482—Coating or impregnation materials
    • C04B2111/00551—Refractory coatings, e.g. for tamping
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof

Definitions

  • This invention relates to an improvement in a lining for a vessel such as ladle or tundish which holds or treats a melt of high density and high temperature, such as molten metal and particularly molten steel, and, more particularly, concerns a method of making such a lining.
  • a vessel which holds or treats molten metals is constructed in such a way that the inner side of a metallic shell is covered with a refractory based on refractory material or heat-insulating material, as a non-consumable lining, and then said non-consumable lining is covered with brick, unshaped refractory and a heat-insulating moulding, each alone or in combination, as a consumable lining which is brought into contact with a melt having a different composition.
  • the lining material of the vessel is preheated by a burner in order that the temperature of the melt may be lowered as little as possible white the melt is held.
  • magnesia One of the materials which is most heat-resistant when used as a conventional lining refractory for melts and particularly molten steel is magnesia, which is comparatively less expensive, but has a large expansion coefficient. Examples of use of magnesia are described in DE-U-7619744 and DE-A-630500.
  • magnesia When magnesia is used for the lining of melt vessels preheating thereof causes, as a consequence of the large expansion coefficient mentioned above, bending and joint breaking of the lining. This tends to loosen it, and therefore, in the presence of conditions such as the impact of receiving the melt, spailing and pressure can cause accidents such as release of the lining and consequent penetration of the melt past the lining. This means that it is difficult and delicate safely to line a ladle or tundish with magnesia refractory. Consequently, mobility in work planning is heavily restricted.
  • An object of the invention is to provide a vessel such as a ladle or tundish for containing molten metals, which does not cause troubles such as bending and joint breaking of a lining during the period from preheating to receiving and holding the melt by carrying out a lining with a specific moulded magnesia lining; and a method for making said moulded lining.
  • the moulded lining is obtained by mixing 65-85% by weight of a magnesia-based aggregate such as magnesia clinker, dolomite clinker, magnesite, spinel, olivin sand and peridotite, and 10-30% by weight of a hydrating inorganic material such as slaked line, quick lime, slaked gypsum, light magnesia, cement, light dolomite, magnesium chloride, magnesium sulphate, sodium phosphate, barium hydroxide, strontium hydroxide, aluminium sulphate, alum and aluminium hydroxide, and if necessary up to 7% by weight of a heat-insulating material comprising refractory fibres and light refractory materials selected from among asbestos, rock wool, slag wool, kaolin fibre, glass wool, alumina fibre, zirconia fibre, magnesia fibre, silicon carbide fibre, perlite, expanded shale and hollow alumina, and/
  • the kinds and mixing ratio of the mixing materials are within the range of said limited values in order that the porosity becomes 25 to 50% while the bulk density becomes 1.4 to 2.0, and with other mixing ratios than the above it is difficult to obtain a satisfactory moulding.
  • the values of said porosity and bulk density show porous and light properties compared with magnesia brick, and therefore if the moulding is provided at the inner surface, as a lining of a vessel for molten metal it maintains high heat-insulating, heat-retaining properties, less heat loss of hot melt, and a smaller drop in temperature of the melt when the melt is received compared with bricks.
  • the bound water of said hydrating inorganic material and the remaining free moisture in said moulding are escaped until the temperature becomes 1000° C and they are offset by the expansion of said magnesia-based aggregate thereby enabling any alteration of dimensions to lie within an expansion of not more than 0.6% and a contraction of not more than 0.3%.
  • magnesia bricks such function and effects are produced thanks to the contraction caused by the decomposition of said hydrating inorganic material. Accordingly, at the time of preheating the lining may not have bending and joint breaking as well as a fear of causing troubles such as release and the insertion of melt.
  • a lesser degree of skill is needed in carrying out the lining and a far shorter period of preheating time will suffice in the case of the same thickness as brick and unshaped refractory.
  • the insulating-material in the mixing materials will be added if it is necessary to enhance the heat-insulating properties of the moulding, but with greater than 7% by weight thereof the refractory property of the moulding will be degraded reducing the useful life of the moulding.
  • the organic fibrous materials are used as an agent for increasing the green moulding strength for safe-guarding the mouldings from accidents such as cracking and breaking by deformation caused when they are squeezed and transferred during the period until they are coagulated.
  • the organic fibrous materials exhibit these effects to a lesser degree than inorganic fibres, but if they exceed 5% by weight the heating strength of the moulding becomes weak with the danger of collapse.
  • a moulding thus made was lined onto refractory bricks of 140 mm thickness in a 30-ton tundish for th'e continuous casting of steel, in dimensions of 400 mm width x 500 mm length x 65 mm . thickness.
  • the Example is with reference to a tundish for the continuous casting of steel, but the moulding according to the invention can of course be used as a heat-resistant, heat-insulating lining for ladles wherein, as with a tundish, the conditions to melt flow and temperature degree are gentle, and besides it can be used even for the walls of refining and heating furnaces.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Organic Chemistry (AREA)
  • Structural Engineering (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Furnace Housings, Linings, Walls, And Ceilings (AREA)
  • Compositions Of Oxide Ceramics (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)

Claims (5)

1. Verfahren zur Herstellung einer Auskleidung eines Behälterts für geschmolzenes Metall aus einer Masse auf Magnesia-Grundlage, dadurch gekennzeichnet, daß 65 bis 85 Gewichts-% der Masse. auf Magnesia-Grundlage und 10 bis 30 Gewichts-% eines hydratisierenden anorganischen Materials mit Wasser vermischt werden und dabei ein 50 bis 60% Feststoffe enthaltender Brei erzeugt wird, der Brei durch Abfiltern mit Absaugen oder Gießen geformt wird und der Formling sodann bei einer Temperatur unterhalb 200°C koaguliert und verfestigt wird, wobei zumindest ein Teil des gebundenen Wassers des hydratisierenden anorganischen Materials entfernt wird und daß der sich ergebende koagulierte und verfestigte Formling eine Rohdichte (bulk density) im Bereich von 1,4 bis 2,0 und eine Porosität im Bereich von 25 bis 50 % aufweist.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß der Verfahrensschritt des Koagulierens und Verfestigens des Breis bei einer Temperatur unterhalb 100°C durchgeführt wird und dabei der größte Teil der freien Feuchtigkeit und ein Teil des gebundenen Wassers des hydratisierenden anorganischen Materials entfernt werden.
3. Verfahren nach Anspruch 1 oder 2, gekennzeichnet durch den Verfahrensschritt, daß bis zu 7 Gewichts-% eines feuerfeste Fasern enthaltenden wärmeisolierenden Materials mit den anderen Komponenten des Breis vermischt werden.
4. Verfahren nach Anspruch 1, 2 oder 3, gekennzeichnet durch den Verfahrensschritt, daß bis zu 5 Gewichts-% eines organischen Fasermaterials mit den anderen Komponenten des Breis vermischt werden.
5. Auskleidung für einen Behälter für geschmolzenes Material, der nach einem in einem der vorhergehenden Ansprüche beanspruchten Verfahren hergestellt ist.
EP19800302225 1980-07-02 1980-07-02 Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters Expired EP0042897B1 (de)

Priority Applications (2)

Application Number Priority Date Filing Date Title
DE8080302225T DE3069065D1 (en) 1980-07-02 1980-07-02 Method of making the lining of a vessel for molten metal and lining so made
EP19800302225 EP0042897B1 (de) 1980-07-02 1980-07-02 Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19800302225 EP0042897B1 (de) 1980-07-02 1980-07-02 Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters

Publications (2)

Publication Number Publication Date
EP0042897A1 EP0042897A1 (de) 1982-01-06
EP0042897B1 true EP0042897B1 (de) 1984-08-29

Family

ID=8187207

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19800302225 Expired EP0042897B1 (de) 1980-07-02 1980-07-02 Verfahren zur Herstellung einer Auskleidung eines Behälters für geschmolzenes Metall und mit dem Verfahren hergestellte Auskleidung eines solchen Behälters

Country Status (2)

Country Link
EP (1) EP0042897B1 (de)
DE (1) DE3069065D1 (de)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FI69259C (fi) * 1982-02-09 1986-01-10 Aikoh Co Form foer blaosformning av infodringen i ett foer smaelt metall avsett kaerl infodringsfoerfarande i vilket naemnda form anvaends och infodringsblandning som anvaends vid naemnda infodringsfoerfarande
DE3306423A1 (de) * 1983-02-24 1984-08-30 Didier-Werke Ag, 6200 Wiesbaden Ungebranntes feuerfestes bauteil in form einer platte fuer die verlorene auskleidung von metallurgischen gefaessen
AU1420183A (en) * 1983-05-03 1984-11-08 Aikoh Co. Ltd. Tundish for steel casting
EP0302976A1 (de) * 1987-08-13 1989-02-15 Consolidated Ceramic Products, Inc. Verfahren zur Herstellung vorheizbarer, isolierender, feuerfester Auskleidungen aus Aluminiumoxid und Mg0 und Verfahren zu deren Verwendung
DE3703136A1 (de) * 1986-07-24 1988-01-28 Didier Werke Ag Feuerfeste, spritzfaehige massen oder feuerfeste ungebrannte formkoerper auf mgo-basis
JP2928625B2 (ja) * 1990-11-22 1999-08-03 ミンテックジャパン株式会社 焼付補修材
GB2352992B (en) 1999-08-05 2002-01-09 Pyrotek Engineering Materials Distributor device
CN117226084B (zh) * 2023-09-12 2024-05-07 中钢集团洛阳耐火材料研究院有限公司 一种减少中间包钢液中氧化铝夹杂物的方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE722159C (de) * 1938-08-02 1942-07-06 Dynamidon Werk Engelhorn & Co Verfahren zur Herstellung von hochfeuerfesten basischen Steinen
BE756874A (fr) * 1969-10-08 1971-03-01 Prost Sa Compositions refractaires a prise hydraulique
LU72865A1 (de) * 1975-06-30 1977-03-07
SE7607681L (sv) * 1975-07-09 1977-01-10 Foseco Trading Ag Forfarande for kontinuerlig gjutning
SE430883B (sv) * 1976-09-27 1983-12-19 Quigley Co Forfarande for att separera och forlenga livslengden hos basiska eldfasta infordringar i basiska syrgasstalugnar

Also Published As

Publication number Publication date
DE3069065D1 (en) 1984-10-04
EP0042897A1 (de) 1982-01-06

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